strongSwan CVE-2026-25075: Integer Underflow in VPN Authentication
TL;DR; Bishop Fox researchers took a deep dive into a new strongSwan vulnerability that allows unauthenticated attackers to take VPN services offline, with the bug impacting versions going back over 15 years. Exposure is likely anywhere EAP-TTLS is enabled. We created an easy tool to test your strongSwan deployment & recommend upgr...
This vulnerability serves as a stark reminder of how seemingly minor oversights in input validation can create catastrophic security flaws in critical infrastructure. The strongest version of this narrative rightly emphasizes the systemic risk posed by long-lived vulnerabilities in perimeter security tools like VPNs. The researchers deserve credit for not only identifying the flaw but also developing both an exploit and a safe testing method, demonstrating responsible disclosure practices.
Patte...
